Windmill
A windmill is a mill that converts the energy of wind into rotational energy by means of vanes called sails or blades.Centuries ago, windmills usually were used to mill grain (gristmills), pump water (windpumps), or both.The majority of modern windmills take the form of wind turbines used to generate electricity, or windpumps used to pump water, either for land drainage or to extract groundwater. Windmills in antiquity The windwheel of the Greek engineer Heron of Alexandria in the first century is the earliest known instance of using a wind-driven wheel to power a machine. Another early example of a wind-driven wheel was the prayer wheel, which has been used in Tibet and China since the fourth century. It has been claimed that the Babylonian emperor Hammurabi planned to use wind power for his ambitious irrigation project in the seventeenth century BCE. Horizontal windmills The first practical windmills had sails that rotated in a horizontal plane, around a vertical axis. According to Ahmad Y. al-Hassan, these panemone windmills were invented in eastern Persia, or Khorasan, as recorded by the Persian geographer Estakhri in the ninth century.The authenticity of an earlier anecdote of a windmill involving the second caliph Umar (AD 634–644) is questioned on the grounds that it appears in a tenth-century document.Made of six to 12 sails covered in reed matting or cloth material, these windmills were used to grind grain or draw up water, and were quite different from the later European vertical windmills. Windmills were in widespread use across the Middle East and Central Asia, and later spread to China and India from there.A similar type of horizontal windmill with rectangular blades, used for irrigation, can also be found in thirteenth-century China (during the Jurchen Jin dynasty in the north), introduced by the travels of Yelü Chucai to Turkestan in 1219.Horizontal windmills were built, in small numbers, in Europe during the 18th and nineteenth centuries for example Fowler's Mill at Battersea in London, and Hooper's Mill at Margate in Kent. These early modern examples seem not to have been directly influenced by the horizontal windmills of the Middle and Far East, but to have been independent inventions by engineers influenced by the Industrial Revolution. Vertical windmills Due to a lack of evidence, debate occurs among historians as to whether or not Middle Eastern horizontal windmills triggered the original development of European windmills.In northwestern Europe, the horizontal-axis or vertical windmill (so called due to the plane of the movement of its sails) is believed to date from the twelfth and thirteenth centuries in the triangle of northern France, eastern England and Flanders.The earliest certain reference to a windmill in Europe (assumed to have been of the vertical type) dates from 1185, in the former village of Weedley in Yorkshire which was located at the southern tip of the Wold overlooking the Humber Estuary.21 A number of earlier, but less certainly dated, twelfth-century European sources referring to windmills have also been found.22 These earliest mills were used to grind cereals. Hollow-post mill In a hollow-post mill, the post on which the body is mounted is hollowed out, to accommodate the drive shaft.This makes it possible to drive machinery below or outside the body while still being able to rotate the body into the wind. Hollow-post mills driving scoop wheels were used in the Netherlands to drain wetlands from the fourteenth century onwards. Tower mill By the end of the thirteenth century, the masonry tower mill, on which only the cap is rotated rather than the whole body of the mill, had been introduced. The spread of tower mills came with a growing economy that called for larger and more stable sources of power, though they were more expensive to build. In contrast to the post mill, only the cap of the tower mill needs to be turned into the wind, so the main structure can be made much taller, allowing the sails to be made longer, which enables them to provide useful work even in low winds. The cap can be turned into the wind either by winches or gearing inside the cap or from a winch on the tail pole outside the mill. A method of keeping the cap and sails into the wind automatically is by using a fantail, a small windmill mounted at right angles to the sails, at the rear of the windmill. These are also fitted to tail poles of post mills and are common in Great Britain and English-speaking countries of the former British Empire, Denmark, and Germany but rare in other places. Around some parts of the Mediterranean Sea, tower mills with fixed caps were built because the wind's direction varied little most of the time. Smock mill The smock mill is a later development of the tower mill, where the masonry tower is replaced by a wooden framework, called the "smock", which is thatched, boarded or covered by other materials, such as slate, sheet metal, or tar paper. The smock is commonly of octagonal plan, though there are examples with different numbers of sides. The lighter weight than tower mills make smock mills practical as drainage mills, which often had to be built in areas with unstable subsoil. Smock mills originated for drainage, but are also used for other purposes. When used in a built-up area it is often placed on a masonry base to raise it above the surrounding buildings. Mechanics Common sails consist of a lattice framework on which a sailcloth is spread. The miller can adjust the amount of cloth spread according to the wind and the power needed. In medieval mills, the sailcloth was wound in and out of a ladder type arrangement of sails. Later mill sails had a lattice framework over which the sailcloth was spread, while in colder climates, the cloth was replaced by wooden slats, which were easier to handle in freezing conditions.The jib sail is commonly found in Mediterranean countries, and consists of a simple triangle of cloth wound round a spar.In all cases, the mill needs to be stopped to adjust the sails. Inventions in Great Britain in the late eighteenth and nineteenth centuries led to sails that automatically adjust to the wind speed without the need for the miller to intervene, culminating in patent sails invented by William Cubitt in 1807. In these sails, the cloth is replaced by a mechanism of connected shutters.In France, Pierre-Théophile Berton invented a system consisting of longitudinal wooden slats connected by a mechanism that lets the miller open them while the mill is turning. In the twentieth century, increased knowledge of aerodynamics from the development of the airplane led to further improvements in efficiency by German engineer Bilau and several Dutch millwrights.The majority of windmills have four sails. Multiple-sailed mills, with five, six or eight sails, were built in Great Britain (especially in and around the counties of Lincolnshire and Yorkshire), Germany, and less commonly elsewhere. Earlier multiple-sailed mills are found in Spain, Portugal, Greece, parts of Romania, Bulgaria, and Russia.In the Netherlands the stationary position of the sails, i.e. when the mill is not working, has long been used to give signals. A slight tilt of the sails before the main building signals joy, while a tilt after the building signals mourning. Across the Netherlands, windmills were placed in mourning position in honor of the Dutch victims of the 2014 Malaysian Airlines Flight 17 shootdown. Machinery Gears inside a windmill convey power from the rotary motion of the sails to a mechanical device. The sails are carried on the horizontal windshaft. Windshafts can be wholly made of wood, or wood with a cast iron poll end (where the sails are mounted) or entirely of cast iron. The brake wheel is fitted onto the windshaft between the front and rear bearing. It has the brake around the outside of the rim and teeth in the side of the rim which drive the horizontal gearwheel called wallower on the top end of the vertical upright shaft. In grist mills, the great spur wheel, lower down the upright shaft, drives one or more stone nuts on the shafts driving each millstone. Post mills sometimes have a head and/or tail wheel driving the stone nuts directly, instead of the spur gear arrangement. Additional gear wheels drive a sack hoist or other machinery. The machinery differs if the windmill is used for other applications than milling grain. A drainage mill uses another set of gear wheels on the bottom end of the upright shaft to drive a scoop wheel or Archimedes' screw. Sawmills use a crankshaft to provide a reciprocating motion to the saws. Windmills have been used to power many other industrial processes, including papermills, threshing mills, and to process oil seeds, wool, paints and stone products. Spread and decline In the 14th century windmills became popular in Europe; the total number of wind-powered mills is estimated to have been around 200,000 at the peak in 1850, which is modest compared to some 500,000 waterwheels. Windmills were applied in regions where there was too little water, where rivers freeze in winter and in flat lands where the flow of the river was too slow to provide the required power. With the coming of the industrial revolution, the importance of wind and water as primary industrial energy sources declined, and they were eventually replaced by steam (in steam mills) and internal combustion engines, although windmills continued to be built in large numbers until late in the nineteenth century. More recently, windmills have been preserved for their historic value, in some cases as static exhibits when the antique machinery is too fragile to put in motion, and in other cases as fully working mills. Of the 10,000 windmills in use in the Netherlands around 1850, about 1,000 are still standing. Most of these are being run by volunteers, though some grist mills are still operating commercially. Many of the drainage mills have been appointed as backup to the modern pumping stations. The Zaan district has been said to have been the first industrialized region of the world with around 600 operating wind-powered industries by the end of the eighteenth century. Economic fluctuations and the industrial revolution had a much greater impact on these industries than on grain and drainage mills, so only very few are left. Construction of mills spread to the Cape Colony in the seventeenth century. The early tower mills did not survive the gales of the Cape Peninsula, so in 1717 the Heeren XVII sent carpenters, masons, and materials to construct a durable mill. The mill, completed in 1718, became known as the Oude Molen and was located between Pinelands Station and the Black River. Long since demolished, its name lives on as that of a Technical school in Pinelands. By 1863, Cape Town had 11 mills stretching from Paarden Eiland to Mowbray. Wind turbines A wind turbine is a windmill-like structure specifically developed to generate electricity. They can be seen as the next step in the development of the windmill. The first wind turbines were built by the end of the nineteenth century by Prof James Blyth in Scotland (1887),Charles F. Brush in Cleveland, Ohio (1887–1888) and Poul la Cour in Denmark (1890s). La Cour's mill from 1896 later became the local powerplant of the village Askov. By 1908 there were 72 wind-driven electric generators in Denmark, ranging from 5 to 25 kW. By the 1930s, windmills were widely used to generate electricity on farms in the United States where distribution systems had not yet been installed, built by companies such as Jacobs Wind, Wincharger, Miller Airlite, Universal Aeroelectric, Paris-Dunn, Airline, and Winpower. The Dunlite Corporation produced turbines for similar locations in Australia. Forerunners of modern horizontal-axis utility-scale wind generators were the WIME-3D in service in Balaklava USSR from 1931 until 1942, a 100-kW generator on a 30-m (100-ft) tower, the Smith-Putnam wind turbine built in 1941 on the mountain known as Grandpa's Knob in Castleton, Vermont, United States of 1.25 MW and the NASA wind turbines developed from 1974 through the mid-1980s. The development of these 13 experimental wind turbines pioneered many of the wind turbine design technologies in use today, including: steel tube towers, variable-speed generators, composite blade materials, and partial-span pitch control, as well as aerodynamic, structural, and acoustic engineering design capabilities. The modern wind power industry began in 1979 with the serial production of wind turbines by Danish manufacturers Kuriant, Vestas, Nordtank, and Bonus. These early turbines were small by today's standards, with capacities of 20–30 kW each. Since then, commercial turbines have increased greatly in size, with the Enercon E-126 capable of delivering up to 7 MW, while wind turbine production has expanded to many countries As the 21st century began, rising concerns over energy security, global warming, and eventual fossil fuel depletion led to an expansion of interest in all available forms of renewable energy. Worldwide, many thousands of wind turbines are now operating, with a total nameplate capacity of 194,400 MW. Europe accounted for 48% of the total in 2009. Windpumps Windpumps were used to pump water since at least the 9th century in what is now Afghanistan, Iran and Pakistan. The use of wind pumps became widespread across the Muslim world and later spread to China and India. Windmills were later used extensively in Europe, particularly in the Netherlands and the East Anglia area of Great Britain, from the late Middle Ages onwards, to drain land for agricultural or building purposes. The American windmill, or wind engine, was invented by Daniel Halladay in 1854 and was used mostly for lifting water from wells. Larger versions were also used for tasks such as sawing wood, chopping hay, and shelling and grinding grain. In early California and some other states, the windmill was part of a self-contained domestic water system which included a hand-dug well and a wooden water tower supporting a redwood tank enclosed by wooden siding known as a tankhouse. During the late 19th century steel blades and steel towers replaced wooden construction. At their peak in 1930, an estimated 600,000 units were in use. Firms such as U.S. Wind Engine and Pump Company, Challenge Wind Mill and Feed Mill Company, Appleton Manufacturing Company, Star, Eclipse, Fairbanks-Morse, Dempster Mill Manufacturing Company and Aermotor became the main suppliers in North and South America. These windpumps are used extensively on farms and ranches in the United States, Canada, Southern Africa, and Australia. They feature a large number of blades, so they turn slowly with considerable torque in low winds and are self-regulating in high winds. A tower-top gearbox and crankshaft convert the rotary motion into reciprocating strokes carried downward through a rod to the pump cylinder below. Such mills pumped water and powered feed mills, saw mills, and agricultural machinery.In Australia, the Griffiths Brothers at Toowoomba manufactured windmills of the American pattern from 1876, with the trade name Southern Cross Windmills in use from 1903. These became an icon of the Australian rural sector by utilizing the water of the Great Artesian Basin. Another well-known maker was Metters Ltd. of Adelaide, Perth and Sydney.Built in 1787 and in operation until 1896, the old Jamestown windmill stands high on Windmill Hill in the center of the island. It is a three-story octagonal structure with a domed cap or bonnet. The bonnet holds the sails and can turn to capture the wind from any direction.The original framework of the mill is made of hand-hewn chestnut timbers. The exterior is sheathed in cedar shingles. The mill is maintained in working condition, and major renovations to repair damage from weather and insects were completed in 2000-2001. A booklet, The Jamestown Windmill, available by download or in pamphlet form, describes the operation and history of the mill.Battery Day will be held this year on Saturday, June 3, 2017. Battery Day will start off with the sound of cannons reverberating across the West Passage. Festivities begin at 11am with the Jamestown Band playing patriotic music and the Newport Artillery firing its cannons from inside the protective earthworks that were originally built by the colony of Rhode Island and Providence Plantations in 1776.The Rhode Island General Assembly ordered the building of the Conanicut Battery in 1776. The original fort was probably a simple, crescent-shaped earthwork designed to house and protect six to eight heavy cannon and their men. The British captured the fort in December 1776 and occupied it until October 1779. They rebuilt the battery in the shape seen today. A ditch surrounds the earthen barricades on all sides. The fort could house heavy cannon to defend the West Passage, and the bastions on the north and south protected it from land attack.In 1916, the military re-acquired the land and built six underground observation posts on the top of Prospect Hill, just east of the 1776 battery. From there, military observers had an unobstructed view of the approaches to Narragansett Bay and of the mine fields laid in the East and West Passages during World War I and World War II.In 1963 the federal government gave the property to the Town of Jamestown, and in 1972 Conanicut Battery was added to the National Register of Historic Place.Since the restoration of the park in 2002, the Jamestown Historical Society has worked with the town to maintain the historic elements within the Conanicut Battery Historic Park. Ever other year, the society sponsors Battery Day to celebrate the history of the park. The park is open from sunup to sundown every day. During the 19th century, the land was farmed.The Conanicut Friends Meeting was established by the Newport Quaker Monthly Meeting in 1684. The original meetinghouse was considerably north of the present meetinghouse, which lies 100 yards south of the windmill on Windmill Hill. The current meetinghouse is a simple rectangular building, built at the same time as the windmill in 1787 and shingled in a manner similar to the larger structure.At the begining of the 19th century, the Quaker community in Jamestown became too small to sustain the meeting and the building fell into disuse. When the Meetinghouse was reopened in the early 1900's for summering Philadelphia Quakers, it was afforded an "indulged" status to offer worship and Quaker services without the responsibilities of committee work (Finance, Ministry and Council, etc) that is expected in year-round Religious Society of Friends' Meetings.The size of our Meeting has waxed and waned over the years, but the Jamestown Quaker community hopes to keep the Meetinghouse and the spirit of Quakerism in silent worship in that simple place as a part of the life of the island, as well as in its history.The meetinghouse was placed on the National Register of Historic Places in 1972, and in 1976-1977, with matching funds from the Rhode Island Preservation Society, the Conanicut Meeting repaired the building. Further restoration was completed in 1997 with a grant from the Champlin Foundations. In September that year, title to the meetinghouse was transferred to the Jamestown Historical Society, with the provision that the meetinghouse would be open to the Conanicut Meeting for worship during the summers.During 2017, the Meetinghouse is open 1-4pm on June 24 and 11am-4pm on September 23 (Smithsonian Museum day). Quaker meeting is every Sunday from May 7 to October 15 at 10:30 and is open to all. Feel free to walk the grounds unless a meeting for worship is in session.condition that “they erect and keep in repair a good windmill for grinding grain.” The windmill was built at once and still stands on its original site.The mill is a three-story building with eight sides. The original framework of the mill is of hand-hewn chestnut timbers. It is shingled on the outside with cedar shakes. A domed cap, or bonnet, rests freely on the gently sloping sides of the building. The bonnet is kept in place only by its weight. The bonnet holds the sails, the wind shaft to which the sails are attached, and the gears that transform the power of the wind into usable energy.For 109 years, until 1896, the mill ground coarse cracked corn to feed animals and finer corn meal for people to eat. In Jamestown, corn meal was usually made from the dried kernels of white flint corn. White flint is a species of Indian corn that is native to Rhode Island. Each kernel has a hard outer layer and low water content. The corn is hard to grind, but makes a fine, floury meal.Fabyan Forest Preserve was once part of the large country estate of George and Nelle Fabyan. They came to the Fox River Valley in the early 1900s and bought a farmhouse and 10 acres on the west bank of the Fox River. Over the following 20 years, they acquired 300-plus acres and developed the property into a fabulous estate they called “Riverbank.” After their deaths in 1936 and 1939, the Forest Preserve District of Kane County purchased the estate for this amazing preserve. On the east side of Fabyan Forest Preserve, on Route 25, stands the majestic Fabyan Windmill. The 68-foot, 5-story structure was originally built by Louis Blackhaus, a German craftsman, between 1850 and 1860. The Windmill originally stood on a site in what is now Lombard, Illinois. In 1914, it was purchased by George Fabyan for about $8,000, and moved here to Riverbank. After many years, the Windmill had fallen into disrepair. Third-generation Dutch Windmill Maker Lucas Verbij was contracted by the Forest Preserve District to tackle the tough job of restoring the Windmill. He was discovered by Preservation Partners of Fox Valley (the non-profit group that oversees care and provides tours of the historic preserve). Millwrights are difficult to find, along with the materials needed to restore such a unique structure. According to Verbij, “The Fabyan Windmill is the best example of an authentic Dutch windmill in the United States. Actually, it's a treasure, and would be the most popular windmill in the Netherlands (we currently have 1,000 windmills). Restoring Fabyan Windmill was as much honor as it was duty. The timing of the restoration project was critical, as the main beams of the tower were strongly rotting. When you hardly have old original U.S. windmills left, preserving what you have is so important.” After years of planning and effort to restore the historic Fabyan Windmill to its original grandeur, including a trip to the Netherlands for authentic timber and gear work, the Windmill made its public debut in June 2005 with a Grand Reopening Celebration. “There is German, Swedish and Dutch millwright work on this Windmill,” states Verbij. “It is one of the few in the world that is restored to operate by natural wind energy.” Roman numeral markings carved into the beams used in original reconstruction are still visible. It took 33 workers mixing concrete by hand to build the foundation. The foundation is 42 inches deep and 26 inches thick. Inside the mill, the beams and shafts are of cypress wood and trimmed with black walnut. New wooden gears were made. At the top, or cap, of the mill is a huge cogged wheel turned by wind blowing against the vanes (blades). The vanes are covered with canvas sails to help catch the wind. The moving cog rotates a shaft running the height of the mill. You can also learn how the windmill operates by taking a tour, available during weekends from 1-4 p.m., May 15 – October 15. There once was a bakery in the basement, something rare for mills. The grinding mechanisms to make flour are restored, although the Fabyan Windmill no longer grinds. Several honors have been accorded Fabyan Windmill. It is listed on the National Register of Historic Places, and it was also honored in 1980 by its selection to be on a US Postal stamp. This 15-cent stamp was part of a series of five American windmills included in a stamp booklet called WINDMILLS USA. Indeed, even the Windmill can tell some of its own tale. A time capsule was discovered in the walls of the mill by construction engineers from Walter Daniels. Documents included the names of persons who proudly worked on the mill in the 1930s as well as the 1960s. A few citizens describe parents and grandparents who were on the lists. The Forest Preserve added another list, information from the year 2004, and placed the time capsule back in its original spot.Blennerville Windmill is a dominant landmark in Tralee Bay, where the town of Tralee meets the Dingle Peninsula. At the Blennerville Visitor Centre you will find the working windmill as well as an exhibition gallery, craft shop and restaurant. The exhibition includes an audio visual presentation, an emigration display and a bird watching platform with telescope overlooking 'Slí na nÉan' ('the Way of the Birds'). Visitors can get up close and appreciate the scale and complexity of the Windmill machinery and can climb to the top of the windmill. Blennerville was the main port of emigration from County Kerry during the Great Famine (1845 to 1848) and was, during those years, the home port of the famous emigrant barque 'Jeanie Johnston'. The visitor centre houses a fascinating display on Irish emigration including models of the infamous coffin ships. View the Tralee Bay Nature Reserve, where migratory pale-bellied Brent Geese can be seen from October to April. They feed on the eelgrass and green seaweeds on the mudflats and graze in nearby fields and saltmarshes when this food is scarce. Birds of the bay include the Turnstone, Ringed Plover, Dunlin, Redshank, Bar-tailed Godwit, Golden Plover and Curlew. The Sloten Windmill (Molen van Sloten) is a reconstructed, working mill from 1847. It is the only mill open to the public in Amsterdam. An audiovisual presentation about Rembrandt's life, called 'Rembrandt in the attic' is shown here. There is also a model called 'Amsterdam and the water', showing the landscape as it was in 1630. The Sloten Windmill is a tower mill, with an octagon from 1847. The mill lies on the outskirts of Amsterdam, on the ring canal and it ensures that the water level in the lower-lying surroundings remains below a specific level, by draining the area. A number of enthusiastic volunteers give a guided tour through the mill. And whenever possible, the miller shows how he turns the mill cap so that the vanes face the wind, how the vanes rotate or how they are stopped, and how he puts the sails in the vanes.We’ve always loved them, there’s something absolutely bucolic about their squat structures, and the gentle creak of their fins as the spin in the natural wind currents. Windmills have been around for a very long time when people first realized it was possible to harness the power of the wind to perform work. Ever since new innovations have been made in the ability to utilize the never-ending source of power that windmills capture. Windmill Day commemorates the origins of the Windmill, and how it’s helped to shape technology and industry in the past and into the future.The idea of capturing the power of wind to perform work isn’t new, and in fact, it goes back far further into history than you might suspect and has sprung up in multiple cultures throughout the world. Heron of Alexandria was the earliest person known to have harnessed the energy of moving air to perform work, using a very primitive device to power an organ. Persia developed more traditional windmills, though they had a different orientation than the ones we typically think of when hearing the word ‘windmill’.Some historians think that the Persian models were the inspiration for the vertical models that were developed in the middle ages. The first evidence of a windmill can be found in Weedley, Yorkshire, England and is said to have been built in 1185. As is commonly depicted in media, they were used primarily to grind grain, and have been for many centuries thereafter. Recently though, there’s been a growing movement to use Windmills in another fashion entirely! The power of the wind can be harnessed to turn giant wind turbines which in turn generate clean, unlimited, renewable energy! Windmills have been around for a long long time, and while they may seem like primitive tech, they’ve moved into the world as hope for a clean future. Along with solar, bio-fuel, and fuel cells, windmills are working to save the environment! Well, you’ve already started by reading up on it! The best thing you can do to celebrate the day is to educate yourself on the history of Windmills and then begin learning how they’re helping us today. If you live in an area that has them, you can even go out and watch them turn, turn, turn… (Are we the only one hearing that song now?) as you contemplate just how important these are to a bright, pollution-free future for our children. One of the best thing you can do in Bruges is to take a beautiful short walk along the ramparts with its windmills. It is nearby the city center, so after discovering shopping places, beers and coffees, this is a great opportunity to escape from the busy city life for a moment.Belgium has a rich mill history. If you check a map of Bruges from the 16th century, you can see there were no less than 23 windmills here! They were part of the town walls since the end of 13th century. Nowadays, there are four remaining mills between the Dampoort and the Kruispoort. External links Category:Windmills Category:Agricultural buildings Category:Industrial buildings Category:Sustainable technologies Category:Timber framed buildings Category:Wind power